(a) Field of the Invention
The present invention concerns a process for cooling a gas in an apparatus for exploiting gases present in the air comprising at least one unit for separating gases present in the air which is operated by compressed air.
(b) Description of Prior Art
the apparatuses for exploiting gases present in the air and in particular their associated units for the separation of gases present in the air, such as oxygen, nitrogen and argon, in known manner of a type with a double distillation column, consume a large amount of energy, such as with respect to the supplying of feeding air which is compressed at a high flow at a pressure generally between 4 and 17.times.10.sup.5 Pa absolute. On the other hand, these units produce a residual mixture containing a high amount of nitrogen which is partially exploited in the apparatus, for example, for partially cooling the compressed feeding air, which should necessarily be cooled, typically at a temperature lower than 20.degree. C., before purifying the compressed air and introducing same in the separation unit.